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Practiced more gas welding - more questions

I did some additional practice tonight. Tonight I used 16 gage steel and an appropriate tip. I used 1/16 rod. I did a few butt welds. They weren't pretty but seemed to be strong. I could not break them after bending back and forth 90 degrees in a vise. Here are a few questions.

Question 1 - My welding store guys seem to know little to nothing about welding. They gave me 1/16 ER70S2 rod for welding 16 gage steel. Is this correct? I know the rod is for TIG. Is it ok for gas?

Question 2 - I could at times keep a pretty uniform puddle. Got the hang of keeping it equal on both pieces. What I'd like to know is what should the diameter of the puddle be? I could vary it quite a lot as I desired. I just don't know what it should be. Is there a general rule. I would imagine it varies with metal thickness.

Question 3 - As I formed the puddle, I could see a little stuff floating on it. Is this normal. Looks to me like it could contaminate. I noticed it mostly when I started the puddle. Does it mean my torch is adjusted wrong or the metal was not clean. I hit the metal with a wire wheel prior to welding and thought it was clean.

Question 4 - Still not sure if I know the Neutral Flame. It seemed that there was the very feathery outer flame that stayed. Then there was an inner cone which I could shrink down to join or become a small well defined almost white cone. This was small only about 1/4 inch long. At this point, it seemed to me that there were only the two. The outer flame and the inner tight cone. Turning up the oxygen beyond this generally increased noise and that tight little cone appeared to shrink. I think the neutral flame is when the inner cone becomes/joins that tight little white one. Is this correct? Or at neutral do I have three distinct areas, the flame the larger cone, and the tight white cone? I am partially color blind so it is possible there could be another cone I am not appreciating.

Question 5 - How much sparks are normal. At times just a few, other times quite a shower. There did not go far or make much noise. The sparks definitely increased when I hit an area that was scaly from a prior weld. Are sparks a general indicator that the metal may have not been clean.

Question 6 - I was dipping the rod in the puddle to melt it. I perhaps was not pulling it back far enough afterward ( though it was out of the flame ) and it would sometimes glow. Is this OK or do I need to bring it farther out.

Question 7 - I see people describing going back and forth or side to side. I only did this a little to adjust the puddle to be symmetrical over the joint. I actually found most of the motion to be in/out to adjust the size if the puddle. Is this OK?

Question 8 - I was surprised at how quick I seemed to have to dip the rod to keep up with the advancing puddle. Also how much rod was melting with each dip. Probably 1/4 inch. Is this OK or am I going to fast. I would estimate that after tacking I could then go continuous for 5 inches in a minute.

Question 9 - I did not clean up the tacks before going over them with the main bead. I got alot of sparking as I went thru them. Should I have cleaned them up? The tacks tend to be dirty with some scale on the surface. Will this contaminate the weld? Is this scale normal or does it indicate a problem with my settings or technique?

Thanks, any input would be appreciated.

Barry

Reply to
BP
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  1. I have used rods the other way round and it doesn't work out as well. From what I understand gas rods have more deoxidisers in them.
2 Puddle varies with thickness as you say but a massive puddle on thin material creates excessive buckling and distortion. It is bad enough with gas welding without making it worse.
  1. Yup you should see the occasional little opaque bit of stuff floating on top. The finish of your finished bead should be smooth and not mottled.
  2. That soft outer envelope is what shields your weld from the atmosphere. It sounds like you have a correct neutral flame. The little cone would be as you describe about a quarter inch long. Too much oxy will harden that cone and burn your weld. ( oxidizing flame) A feather produces too rich a flame ( reducing flame) and injects extra carbon into the metal creating a brittle weld.
  3. Sparks are too much oxy, you're too close, or like you suggest some dirt.
  4. Keep the tip red. Pull it out and it gets oxidized by the atmosphere. It should not leave the larger envelope of your torch.
  5. / 8. The control of size of puddle and location is controlled by both torch AND rod Moving closer or slowing down makes the puddle larger. Increase the dipping action and the puddle is chilled by the rod reducing its size. Once you are on to a rhythm just keep it up and charge ahead. If you move too fast then your puddle will reduce and your rod will stick.
  6. If you are really picky you grind your tacks. Hesitate over the tack and remelt it completely before moving on. Best of luck, Randy

Reply to
Randy Zimmerman

At my school we use 3/32" ER70S6 for both tig and gas welding. It seems to work fine but I haven't tried anything else.

atmosphere.

atmosphere.

Reply to
AL

The rod your using is fine for oxy. The thing to remember is you can use tig rods for tig and oxy but you can only use oxy rods for oxy and not tig. The oxy rods do not contain sufficient deoxidizers for tig welding.

Typically you try to keep the heat input as low as possible so the slower you travel and the wider the weld the more heat you are putting in the metal and its going to distort.

The stuff you see floating is probably copper deposits. There is a copper coating on the wire to basically keep it from rusting, and when you melt the wire this floats out to the surface of the weld.

Your flame seems ok. Keeping the tip in the shielding of the flame is not a big deal with oxy because oxidation is not a concern, after all your using oxygen to weld, so a little bit on the tip isn't going to make any difference. The problem is though that the oxidation that does occur at the tip when when it cools, the tip now requires a higher temp to melt cause of the oxidation. Much more fluid to leave it within the flame envelope.

Sparking is generally from to much oxygen or having your tip too close to the metal. Also have to be careful of flashback if you dont have a flashback arrestor.

Reply to
IceClampers

I like to use very soft rod, I don't know the designation, it's been years, but it's very mallaeble steel, good for gas welding mild steel. This flows much better than ER70, etc.

Reply to
David Algie

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